Why Does Misfire Happen When Starting A Car? Let’s Find Out!

Last Updated on May 10, 2024 by Azim Uddin

Regardless of your car’s model, how carefully you drive, or how often you have it inspected, your car’s engine can misfire unexpectedly while you are on the road or starting your car.

So, what causes misfires when starting car? Several potential reasons can cause your car’s engine to misfire while you try to start it, including:

• A damaged turbocharger
• A clogged air filter
• Cracked ignition coils

In this article, we will talk about the reasons why your car’s engine misfires when you try to start it. Additionally, we will provide solutions to this issue. So let’s get started!

Misfire When Starting Car: Common Causes And Possible Solutions

Below, we have listed the possible reasons why your vehicle might be misfiring when you start it.

The turbocharger in your car is damaged

Most modern cars with diesel engines or petrol engines have a device called a turbocharger. This device has a compressor that uses energy from your car’s exhaust gasses to do the following:

• Draw in a large amount of air.
• Compress the air.
• Transfer it into the intake manifold.

This, in turn, causes the following things:

• A large volume of pressurized air enters the cylinders in your car’s engine.
• Your car engine generates more power.
• The fuel in your car burns more efficiently due to complete combustion.

If the turbocharger in your car is damaged, it cannot effectively transfer compressed air to the cylinders. Thus, the fuel in your car burns incompletely. So, it could be the reason your car’s engine misfires while you try to start it or speed up while driving.

Solution

Your car’s turbocharger can malfunction in various ways, such as:

• The bearings inside it can develop corrosion.
• The compressor may get damaged.
• It can develop leaks.

Thus, you should take your car to a mechanic and get the turbocharger checked properly. You might need to replace this device if the mechanic detects a significant issue in it. But if there are just small cracks or damage, the mechanic can probably fix it for you.

The air filter in your car is packed with dirt

Your car operates smoothly when the fuel in it chemically reacts with the air entering the engine to produce heat energy. The air filter in your car filters the atmospheric air entering your car’s engine. So, it ensures that enough clean air enters the engine.

Look at the picture we have provided above. Here, you can see that trapped dirt causes clean air filters to become clogged. When the air filter in your car gets packed with dirt, the following things occur:

• Your car consumes more fuel because more fuel is present in your vehicle than clean air.
• Your car’s engine produces less power than before.
• Unfiltered pollutants damage the sensors in the engine intake manifold of your vehicle.
• Your car’s engine often misfires when you try to start it.
• Your automobile can’t accelerate properly.

Solution

To solve this issue, you should remove the dirty air filter from your car and clean it with an air filter cleaner available at automobile stores. Check out the steps below to learn how to clean an air filter.

• Step 1: Lift the hood of your vehicle.
• Step 2: Try to locate the black-colored air filter box around your car’s engine.
• Step 3: Open the air filter box by removing the clips attached to the cover of the box.
• Step 4: Use your hands to gently slide out the air filter from the air filter box.
• Step 5: Tap the back of the air filter with your hand to remove loose dirt.
• Step 6: Then, spray both sides of the filter generously with air filter cleaner.
• Step 7: Wait for 10 minutes.
• Step 8: Now, spray water on the dirty air filter at low pressure.
• Step 9: Keep rinsing the air filter until all the residue from the cleaner washes away.
• Step 10: Now, use a fan to air-dry your air filter.
• Step 11: Use a squeeze bottle to apply new air filter oil to your clean air filter.
• Step 12: Wait for 20-25 minutes, and then reattach the air filter in your car.

For a visual representation of this process, you can watch this YouTube video.

The ignition coils in your car have sustained damage

The ignition coils in your car is made of the following:

• An Iron core
• A primary winding
• A secondary winding
• Isolation materials

When the current flows from your car’s battery to the primary coil,  a magnetic field gradually forms around the coil. During ignition, the knife switch opens and causes the coil to lose current. As a result, the magnetic field around it collapses.

This generates a voltage of about 45,000V in the primary winding. Then, this voltage is transferred to the spark plug through the secondary coil. The spark plug uses this voltage to ignite the fuel and air in your car.

If your vehicle has damaged ignition coils in it, this process will not occur smoothly. If your car has cracked ignition coils, you will notice the following symptoms:

• The check engine light will flash on your car’s dashboard.
• Your engine will misfire while starting or operating.
• Your car’s steering wheel will shake while you are slowing down.
• Your car’s catalytic converter will overheat often.

Solution

First, remove the ignition coils from the top of your car’s engine. If you notice that the ignition coils look dirty and have oil and soot marks, you can easily clean them with an electronic cleaner.

However, if you notice large cracks on the ignition coils, you should replace them with new ones. It will cost you around $100-$300 to install new ignition coils in your car.

For more information on faulty ignition coils, you can watch this YouTube video.

FAQs

Read the FAQs we have given below to gain more information about why your car’s engine misfires when you try to start your car

Q: How does frequent engine misfiring affect my car’s performance?

If your engine keeps misfiring often, your car’s performance will deteriorate.  It will cause your vehicle to lose power, use more fuel than normal, emit more  carbon dioxide and nitrogen monoxide, and damage the engine.

Q: If I use poor-quality fuel in my car, will my car engine misfire?

If the fuel in your car contains a higher percentage of ethanol compared to octane, it can cause incomplete combustion. Thus, due to improper combustion and engine lubrication, your car’s engine might misfire when you try to start it.

Final Words

Overall, your car engine can misfire at any time, whether you are trying to start your car, accelerate, or decelerate. This happens when an internal component of your car malfunctions and prevents complete combustion in the cylinders of your car’s engine. Your car engine will misfire if it has a damaged turbocharger, clogged air filter, or bad ignition coils. Thus, you should regularly check these components in your car to keep them in good condition.